The disclosure generally relates to low attenuation optical fibers suitable for dense wavelength division multiplexing (DWDM).
Low attenuation is an important characteristic of standard single mode optical transmission fibers configured to efficiently transmit data over long distances. To increase the information capacity, multiple wavelength transmission technology using dense wavelength division multiplexing (DWDM) is being used with these fibers.
Optical fibers for long haul DWDM applications are currently operated in the C band (1530 nm to 1565 nm) and L band (1565 nm to 1625 nm). The standard single mode transmission optical fiber utilized in these applications has a cable cutoff wavelength below 1260 nm and is optimized for transmission in both the 1310 nm and the 1550 nm wavelength windows. These fibers are also used in L band applications, although they suffer from relatively high bend losses in the 1625 nm wavelength range. For long wavelength bands above the L band, the bending performance of these fibers is further compromised due to very large macro and micro bend induced losses. Thus, typical optical transmission fibers designed to operate within C and L bands have not been utilized in the 1625 nm to 1675 nm wavelength range because they suffer from very high bend induced losses within this wavelength range.